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<table width="100%" summary="page for ozone"><tr><td>ozone</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Monthly ozone measurements over Central America.</h2>

<h3>Description</h3>

<p>This data set is a subset of the data from the 2006 ASA Data expo
challenge, <a href="http://stat-computing.org/dataexpo/2006/">http://stat-computing.org/dataexpo/2006/</a>. The data are
monthly ozone averages on a very coarse 24 by 24 grid covering Central
America, from Jan 1995 to Dec 2000. The data is stored in a 3d area with
the first two dimensions representing latitude and longitude, and the third
representing time.
</p>


<h3>Usage</h3>

<pre>
ozone
</pre>


<h3>Format</h3>

<p>A 24 x 24 x 72 numeric array</p>


<h3>References</h3>

<p><a href="http://stat-computing.org/dataexpo/2006/">http://stat-computing.org/dataexpo/2006/</a>
</p>


<h3>Examples</h3>

<pre>
value &lt;- ozone[1, 1, ]
time &lt;- 1:72
month.abbr &lt;- c("Jan", "Feb", "Mar", "Apr", "May",
 "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec")
month &lt;- factor(rep(month.abbr, length = 72), levels = month.abbr)
year &lt;- rep(1:6, each = 12)
deseasf &lt;- function(value) lm(value ~ month - 1)

models &lt;- alply(ozone, 1:2, deseasf)
coefs &lt;- laply(models, coef)
dimnames(coefs)[[3]] &lt;- month.abbr
names(dimnames(coefs))[3] &lt;- "month"

deseas &lt;- laply(models, resid)
dimnames(deseas)[[3]] &lt;- 1:72
names(dimnames(deseas))[3] &lt;- "time"

dim(coefs)
dim(deseas)
</pre>


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